// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System.Collections.Generic;
 
namespace Microsoft.Build.TaskHost.BackEnd;
 
/// <summary>
/// This class provides helper methods to adapt from <see cref="NodePacketValueFactory{T}"/> to
/// <see cref="ObjectTranslator{T}"/>.
/// </summary>
internal static class TranslatorHelpers
{
    /// <summary>
    /// Translates an object implementing <see cref="ITranslatable"/> which does not expose a
    /// public parameterless constructor.
    /// </summary>
    /// <typeparam name="T">The reference type.</typeparam>
    /// <param name="translator">The translator.</param>
    /// <param name="instance">The value to be translated.</param>
    /// <param name="valueFactory">The factory method used to instantiate values of type T.</param>
    public static void Translate<T>(
        this ITranslator translator,
        ref T instance,
        NodePacketValueFactory<T> valueFactory)
        where T : class, ITranslatable
    {
        if (!translator.TranslateNullable(instance))
        {
            return;
        }
 
        if (translator.Mode == TranslationDirection.ReadFromStream)
        {
            instance = valueFactory(translator);
        }
        else
        {
            instance.Translate(translator);
        }
    }
 
    private static ObjectTranslatorWithValueFactory<T> AdaptFactory<T>(NodePacketValueFactory<T> valueFactory)
        where T : class, ITranslatable
        => static (ITranslator translator, NodePacketValueFactory<T> valueFactory, ref T objectToTranslate)
            => translator.Translate(ref objectToTranslate, valueFactory);
 
    public static void TranslateDictionary<T>(
        this ITranslator translator,
        ref Dictionary<string, T>? dictionary,
        IEqualityComparer<string> comparer,
        NodePacketValueFactory<T> valueFactory)
        where T : class, ITranslatable
        => translator.TranslateDictionary(ref dictionary, comparer, AdaptFactory(valueFactory), valueFactory);
}